01638 428 974


Immersion Controllers

 There are many immersion controllers on the market, this is because when used correctly they can save householders hundreds of pounds a year in water heating costs, and extend the life of a boiler or air source heat pump. They do this by diverting excess solar energy to the immersion to heat up the water.

The problem with immersion controllers is that the vast majority are not being used as efficiently as they should be, as customers are not being fully educated in what is becoming an increasingly busy industry.
Most people are aware that an immersion controller can sweep up excess energy after the household usage and battery storage requirements have been met. However, this is only part of the story.

The immersion controllers heat the tank to the temperature setting on the thermostat, so if for example you have your hot water set to heat up between 5am and 8am, but you are all out of the shower by 7am, it is likely that your gas, oil, or heat pump system will have heated the water and left the immersion controller nothing to do.

Hot water will stay hot for around three hours in a modern tank. To avoid the problem outlined above you should want to set your hot water to be heated between 2am and 5am. This prevents the immersion controller sitting idle all day, with a Tank Hot message on the screen.

But much more substantial gains can be made with one of the more sophisticated immersion controllers which also come with immersion timers.

If you read our page Solar Energy Tariffs, you will find that free or very inexpensive electricity is available from the grid, and used by thousands of solar panel system owners every morning. For a full description of this visit our Solar Energy Tariffs page.


It is fair to say many people are not using their current hot water heating system anymore, they instead set the timer on their immersion controller to heat the water using the grid, between 1am and 5am each morning. Often, they are being paid to do so.

Once you have seen the benefits of one of the more sophisticated models, this narrows your options to four models of immersion controllers, having fitted thousands of these controllers over the years we believe the myenergi eddi offers the most, and more importantly it is incredibly reliable.

Immersion controllers are not expensive and often pay for themselves in a year or two.
Green Solar World is not affiliated with myenergi.

Why Eddi Immersion Controllers?

 Green Solar World is not affiliated with myenergi.